Furnace electrode



April 2, 1929. P. L. J. MIGUET FURNACE ELECTRODE Filed Feb. 9, 1927 A lll.

Patented Apr.l 2,. 1.929.

UNITED STATES PATENT orFIcE.

ravi. Louis Josera incoar, or snJULiEN-nnnnuninnnn, lamina, usmNoR 'ro socrn'inntncrnonzrnmonereun DE moN'rRrcHrER, or lrfmrnmnmmom- ENNE, FRANCE.

rammen ELnc'rnonn .application 'mea rbiaryaiaar, 'serial No. manzana in France meest-r ai, 192s.

This. invention relateslto improvements'in electrical `furnaces `and especially improve'- lments in electrodes for such furnaces, and is an .improvement on aelectrodes of the ty e l 5 described and claimed in my application or Letters Patent of the United States tiled September 29, 1926, Serial No. 138,540.

The object of the present invention is to provide an improved electrode comprising a hollow frame, a conductive continuous hollow Vcylindrical body composed of coupled sectors each separately mounted on and secured to said'i'rame and a core which fills the central -boreor channel formed in said frame and vwhich may be formed as a part of the working charge'of, the '.t'urnace'inv which the electrode is used and said core may be composed of nonconductive material such as silica, in which event no current passes therethrough, or maybe formed of conducting material such as carbon, in which/latter case an insulating layer is interposed between said sectors and Said core or filling mass.

` One specicobject of the present invention is to effect improvements` in the construction z ofthe' frame to which the sectors are secured.

Another object` is to eiect improvements in the construction of the sectors.

Another object is to eiiect improvements in the means for detachably securingthe sectors to the frame. y A

Another object is to nents in the construction of the electrode as an entirety, composed of the frame andthe sectors, as to greatlyfacilitate the assembling and disassembling of the various parts or' which the-electrode is composed.

With the above and other objects inview,` the invention consists in the construction, Y

combinationy and arrangement of devices hereinafter describedand claimed.

The invention will be described with ref-- erence to the accompanying drawings:

Figs. 1 and 2 are respectively a sectional elevation and a sectional plan of a circular continuous electrode obtained by piecing together sectors staggered relatively to each other and mounted onva metallic interior frame; y

Figs. 3,4 and 5 are respectively a sectional elevation of an electrode for reduction or electrolysis", the internal mass or core of which is accessible to the current which :flows to the base of the furnace wherein said electrode is arranged; asectional elevation of a similar electrode,the internal mass or core of which 1s not accessible to the current, said electrode being disposed in a furnace similar to that referred to; and a sectional elevation ei a similar electrode, the internal mass or core of which is accessible to the current, said electrode being disposed in a furnace such as described invmy application No. 121,189 for Letters Patent of the United States and in which the current passes towards the lateral walls.

Fig. 6 is a transverse section of an electrode with a filling mass or core having lateral pro- ]ections, .said mass being constituted either wholly or partly of raw materials.

Fig. 7 is a sectional view of a modified form of the invention' provided with an inby, means of bolts 41 on rings 42, which are connected together by uprights 43. Grooves or radial spaces 44 are provided between the assembled sectors, 'and are filled afterwards with clay or cement. The sectors of each vertical row are connected together, end to end,

, Aby dovetailedljoints 20. This construction effect such improve-v.

greatly facilitates the assembling and disassembling of the sectors, and their attachment to'and detachment-romthe frame. The electrode thus constructed forms a closed bundle, of straightline form, in which superheating and accumulations of gases are avoided by rendei'ing the filling mass or core 45 inaccessible to the current, said mass forming only -an interiorprotection, and said bundle having the same absolute transverse section as that of the knownkind and allowing the same density of current, which may vary, in case of reduction and according to the chosen material, between 4 and 5 ampeles per square centimeter.

Such construction permits lateral ex- .pension of' the current without change of the composition of the filling mass and without interposition of an insulating layer, ensures really the practical isolation of said filling mass so that no current passes therethrou h. Experiments have shown, that the density of current, with regard to the entire .sectionl ios of the electrode should be decreasedto about 2 amperes persquare centimeter and secondly` that the transversesec'tion of the filling mass should not be much reater than that of the sectors, so that, finali said sectors. are submitted, considering that superheating and gaseous accumulations near the aX'is must be avoided, to a current of 4 and 5` ampercs per square centimeter, in the same manner as the straight-line bundles.

In the form of the invention shown in Figure4 3 the filling mass 45 is of conducting material and hence current passes therethrough as well asv through the hollow cylindrical conductin body formed by the sectors 1,9, the lines 0% the current being indicated at 46.

In the form of the invention shown in Figure'4, an insulating cylinder 48 is interposed between the filling mass of conducting material 45 and the carbon sectors so that current is prevented from passing through the filling mass.

In the form of the invention shown in Figure 5, the filling mass 45 is of nonconducting material, vwhich may be the same as of the working charge in the furnace and the distribution of the current 46 occurs principally in the-heterogeneous fusion bed. In all of y the forms of the' invention superheating and gaseous accumulations near avoided. D

Superheating and axial gaseous accumuthe axis are lations are especially liable to occur in very large electrodes, but these are avoided by my invention which operates to maintain the current near the periphery.

vIn lFigure 6 I illustrate another modified form of the invention in Awhich radial inwardly openings in recess49'fare formed between the carbon filled with the same material as constitutes the filling core 45. the material of the filling mass to somewhat closely approach the periphery of the electrode and is especially important when the electrode is used in treating aluminum, in which fiuor, produced by electrolysis must be retained by alumina and carbon contained in the filling mass.

In Figure 7 I show a modified form of f electrode of substantiall the kind shown in Figure 6, but in the interior of which is placed an insulating envelope 48. This insulating envelope may be only a simple layer of insuating varnish or other appropriate material applied as an insulating coating or paint, against the internal surface of the sectors and the metallic pieces or parts assembling the same or may be otherwise suitably constructed.

sectorsdlgfand which are- This construction causes ber or bore formed in sai frame.

2. An electrode for electric furnaces comprising a hollow frame, a conductive continuous exterior body formed by coupled sectors individually mounted on the outside of said frame, and a mass of material filling the central chamber or bore formed in said frame.

3. An electrode for electric furnaces, com

,prising a hollow frame, a conductive contin- -uous body,

formed by coupled sectors individually mounted on the outside of said frame, a mass v.of conductive material filling the central channel formed in said frame, and means for preventing current from passing .through the filling mass.

4. An electrode for electric furnaces, comprising a cylindricaly hollow metallic frame, carbon sectors joined together and individuall mounted on the outside of said frame, bells -for connecting each of said sectors to said frame andv a` core, fillin .the central chamber or b ore formed in sai frame.

5. An electrode for electric furnaces, comprising'a cylindrical hollow frame, a conductive exterior body formed by sectors joined together andindividually mounted on the outside of said frame and provided with radial grooves on their inner sides, and a i massv of material fillingv the central channel formed in said frame and said grooves.

6. An electrode for electric furnaces, comprising a hollow frame, a conductive continuous exterior. body formed by coupled sectors individually mounted on the outside of said frame, a'mass of conductive material filling the central channel formed in said frame and an insulatinglayer interposed between said frame and said filling mass.

7. An electrode for electric furnaces comprising a hollow frame, a conductive continuous exterior body formed by coupled sectors individually mounted on the outside of said roviding rame and radial grooves on the inner face o said body, a filling mass, constituted in part by the working material intervening in the reduction process performed in the furnace, said filling mass being arranged in the central channel formed in said frame and in'said grooves, and means for preventing current from passing through said filling mass.

In witness whereof I afiix my signature.

PAUL LOUIS JOSEPH MIGUET. 

